Base



FIG. 1 is a left, top, front perspective view of a base embodying our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a left side elevational view thereof, the right side elevational view thereof being a mirror image of the left side shown;

FIG. 4 is a rear elevational view thereof; and,

FIG. 5 is a top plan view thereof.

The broken line representations in the figures are for the purpose of illustration only, and form no part of the claimed design. 

CLAIM The ornamental design for a base, as shown and described. 